Throughout the novel, Piranesi personifies The House, which is what he calls the surreal distributary world in which he lives. Take, for example, this passage from the beginning of the novel:
A great Hand of Water reached out to pluck me from the Wall. I flung my arms around the Legs of the Woman carrying a Beehive and prayed to the House to protect me.
[...]
Then, just as suddenly as it began, it was over. The Joined Tides swept on into the surrounding Halls. [...]
I realised that I was holding on to something. I opened my hand and found a marble Finger from some Faraway Statue that the Tides had placed there.
The Beauty of the House is immeasurable; its Kindness infinite.
In this scene, Piranesi has nearly drowned in a flood. He personifies the water as a "Hand" which "pluck[s]" him out of place. He prays to the House for protection and, once the tide ebbs away, he perceives the finger as a sign of its benevolence, intentionally "placed there" by the water. In this way, Piranesi shows how he thinks about the world and all its elements as having human-like (or even god-like) agency. This is also communicated by his use of capital letters, which name inanimate beings with a formality usually reserved for people. This scene also demonstrates the reciprocal nature of Piranesi's relationship with the House; he speaks to the House, and through signs, symbols, and actions, the House speaks back.